Two different collectors sent in copies of the following British Small
Arms Training pamphlet.

Contained in the 1942 edition is the drawings of a spotlight projector,
more commonly known as a flashlight mount. The spotlight mounts to the muzzle of the
Thompson and is actuated by contact with the trigger.

It appears from Fig. 6 that the clip leads are mounted to the receiver
frame just in front of the buttstock. The second lead is clipped around the rear pistol
grip.

When the trooper's hand contacts the rear grip and then touches the
trigger the circuit is completed and the spotlight turns on.